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Intrauterine growth retardation: morphometry of the microvillous membrane of the human placenta.

The syncytiotrophoblast microvillous membrane of the human placenta has been investigated with quantitative analyses in cases of severe fetal growth retardation associated with a marked reduction in the surface area of exchange at the peripheral villous level. This study has shown that, in placentae of intrauterine growth-retarded infants of unknown origin, there were morphological changes in the microvillous membrane characterized by an increase in the microvillous surface density and surface enlargement factor, associated with a reduction of the intermicrovillous space. It is not possible to state whether these morphological changes represent a delayed maturation of the placental tissue, or compensatory mechanisms to improve the functional efficiency of the placenta. In pre-eclampsia, these placental changes were much less pronounced, possibly due to severe uteroplacental ischaemia in this complication of pregnancy. Despite these morphological changes, both groups of placentae showed significant reductions in absolute values for the microvillous and total trophoblastic surface areas, which can have major implications on the functional efficiency of the placenta.

Birth Weight↗

PubMed1996

Structure, functional and cerebral asymmetry: in vivo morphometry of the planum temporale.

Using high-resolution magnetic resonance (MR) imaging, the normal left-right asymmetry of the planum temporale (PT) can be quantified accurately and reliably in the intact human brain. The following main results have emerged from MR measurements of individual direction and degree of PT asymmetry. (1) Normal left-handers are less left-lateralized than normal right-handers, without significant gender effects. This confirms a structural-functional correlation in cerebral asymmetry. (2) The aforementioned handedness difference in PT asymmetry is also found in pairs of normal monozygotic twins discordant for handedness. Thus, structural brain asymmetry may not be genetically determined. (3) Whereas right-handed patients with developmental deficits of phonological processing have been reported to show decrease PT asymmetry, musicians with perfect pitch display exaggerated leftward asymmetry. Thus, increasing leftward asymmetry of auditory-related cortices covering the PT may be correlated with the processing capacity for certain auditory features. Studies of the PT as a structural marker of cerebral asymmetry will continue to contribute to a better understanding of the phylogeny and ontogeny of laterality.

Cerebral Cortex↗

PubMed1981

A computer system for combined neuronal mapping and morphometry.

A computer system has been developed which allows both mapping and planimetry of histological preparations. Data consist of cytoarchitectonic boundaries defined in low-power micrographs of thick sections, and nuclear and vascular profiles defined in high-power micrographs of semi-thin sections taken from the original thick tissue, and landmarks common to both. Data from these different preparations and magnifications are entered into the computer on a digitizing tablet and are stored as points in a real-world coordinate system, along with profile labels, landmarks for alignment purposes, and section depth. Subsequent programs determine parameters such as area and perimeter for each profile, as well as its geometric center and relationship to the cytoarchitectonic boundary. This mapping parameter allows morphometric analysis of profiles as a function of their position. Other programs allow display and manipulation of data in 3 dimensions, cell counts, and stereology. Data acquisition is done in the laboratory, using a micro-computer; analysis and display are done on a large time-sharing computer connected to the small machine by a telephone interface.

Animals↗

PubMed1982

A structured program in BASIC for the analysis of peripheral nerve morphometry.

The BASIC program developed for use on a M.S.I. 6800 microprocessor analyses cross-sectional measurements of fibre (D) and axon (d) calibre made on electron micrographs of suitable magnification. Data input routines cover measurements of area and diameter, made manually or presented as fully computed values printed out by a M.O.P. Separate sub-routines input digitized data from a digitizer tablet coupled to the microprocessor. Myelin sheath thickness (2M) (D-d), or area and 'g' (d/D) are derived. The two analytical programs provide either frequency distributions, with associated statistics for each parameter, or analyses of the relationships (D:d), (d:2M) and (D:g). The highly structured nature of the program permits it to be edited or extended according to the project. The main programme controls the overall flow of analysis; discrete subprograms inserted into the main program perform the data input, parameter derivations, data checks and analyses. This system offers maximum flexibility and is suitable for most morphometric investigations involving peripheral nerves.

Animals↗

PubMed1983

The image-combining computer microscope--an interactive instrument for morphometry of the nervous system.

The image-combining computer microscope is a new configuration of light microscope and computer graphics instrumentation which provides remarkable morphometric capabilities over a wide range of applications. The key component is the well known camera lucida, an image-combining device that is used to superimpose the computer graphics image upon the microscope's image of the object under study. Illumination need not be limited to the bright-field variety. The image superposition permits the investigator to study the object and acquire data from it while always looking through the microscope oculars. A computer controlled stepping motor driven stage is integrated with translations of the graphics image to permit image superposition and data acquisition at maximum visual magnification over the full expanse of a 25 X 25 mm tissue section. The investigator controls the system by means of a graphics tablet and a "Menu" area visible to him in the microscope's field of view. Spatial data in all 3 dimensions can be acquired easily since the z-axis is also stepping motor controlled. EM micrograph transparencies can be studied similarly. Stereological applications are possible by superimposing test grids upon the image. The system is self-contained and carries out data analysis programs written in C or Basic. Simplicity of operation has been emphasized throughout.

Animals↗

PubMed1984

A structured program in BASIC for cell morphometry: its application to the spinal motoneurone.

The BASIC program developed for use on an RML380Z computer collects, sorts, corrects and analyzes counts of organelle number, and measurements of membrane length and profile area. These fundamental parameters are used to derive intermediate parameters and their interrelationships are examined. Data input routines permit either measurements obtained from a digitizer tablet or the use of non-automated methods. A main program controls overall program flow and discrete sub-programs implement data input, data checking, derivation of parameters and analyses. The program is applied here to analyses of motoneurone synaptology, but with simple adaptation may be used to analyze other cell types.

Animals↗

PubMed1986

Morphometry of size/volume variables and comparison of their bivariate relations in the nervous system under different conditions.

Comparison of the different approximation equations and procedures to estimate the volume of a brain region with an irregular shape contained in parallel sections indicates that the 'basic volume estimator' using systematic section is very efficient and sufficiently accurate. Important in estimating the volume is the correction for shrinkage and the accuracy of the section thickness determination. Methods to estimate thickness of section are outlined, and the method of differential focusing is discussed. In the Appendix, the corrections are described for overestimation of the volume by overprojection of the cross-sectional area and underestimation by underprojection when the size of cross-sectional area changes non-negligibly within sections. Statistical techniques to compare bivariate linear relations of different groups are reviewed. Emphasis is laid on Model II regression techniques that are used when the two variables considered are both subject to biological variation and measurement error. A new Model II procedure is proposed to compare the coincidence of the slopes of bivariate distributions and to test whether or not an experimental bivariate sample deviates significantly from a control sample when only the control group shows a significant bivariate linear relationship.

Animals↗

PubMed1989

Nerve fibre morphometry: a comparison of techniques.

This study compared different approaches to measuring nerve axon and fibre diameters and areas from transverse sections. A mock photomicrograph and mock tissue section, each with 100 identical, circular 'fibres' was constructed. Three measurement protocols were investigated: (A) circular approximation from minimum diameter; (B) circular approximation from the mean of orthogonal diameters; and (C) calculation of diameter and area from a digitized circumference. For each protocol, all 100 fibres on the photomicrograph were repeatedly measured using a digitizing tablet. Similarly, the fibres on the mock tissue section were measured using a digitizing tablet and microscope with camera lucida. The variance for these data was calculated. Protocols were compared on the basis of variability and the amount of digitizing time required. For diameter measurements, protocol B showed significantly lower variability than A or C (P less than 0.05), with only a modest increase in digitizing time over A. For area measurements, protocols B and C showed significantly lower variability than A (P less than 0.05), again with a modest increase in digitizing time. Measurements made using the microscope and camera lucida showed significantly lower variability than those made from the photomicrograph, but took more time. These data suggest that for diameter measurements, a mean of orthogonal diameters approach is best, and that for area measurements, a traced circumference approach is best as it is more flexible than the orthogonal diameter approach. While the microscope and camera lucida setup is more time-consuming to use, it eliminates the need for photomicrograph production.

Animals↗

PubMed1989

Morphometry of peptide-containing nerves in gut muscle layers: a quantitative approach to the study of autonomic neuro-muscular junctions.

A method for the quantitative assessment of peptide-containing nerves in the gastrointestinal muscle layers is described. Tissue samples are sectioned obliquely, at 45 degrees, in the plane bisecting the long axes of longitudinal and circular muscle fibres, and peptide-containing nerve fascicles are revealed by immunofluorescence. Cross-sectioned fascicles are counted (number/area of muscle) and their length density per volume of muscle layer is calculated. The composition of immunostained nerve fascicles is also assessed, by counting peptide-containing fibres in each, while peptide transmitter co-distributions are studied in parallel using adjacent tissue sections. Thus, the approach described provides a means for the delineation of both quantitative tissue distribution and composition of autonomic neuro-muscular junctions in the gastro-intestinal tract.

Animals↗

PubMed1995

Interpreting nerve morphometry data after experimental traumatic lesions.

Morphometric data were obtained in 2 experimental conditions: crush lesions of the sciatic nerve of rats, and transection of this nerve followed by repair. Ratios were used in order to facilitate comprehension of data. Results were compared to those obtained using a method of functional assessment. The study indicated that morphometric data provided a reliable picture of the trophic condition of regenerated nerves but did not correlate with the level of function.

Animals↗

PubMed1994

Computed detection and quantitative morphometry of Alzheimer senile plaques.

Senile plaques (SP) are the most characteristic neuropathologic lesions of Alzheimer's disease (AD) and studies of plaque cortical distribution, density, and morphology may lead to new information about the origin and pathogenesis of this disease. We have developed an automated computer image analysis program to detect SP (including diffuse and mature forms) and to measure SP size, shape, and fractional area or load in digital micrographs of silver-stained tissue sections. The plaques are detected with adaptive thresholding, requiring no user interaction. Measures of SP size, morphology, and load are readily calculated from the pixel values in the detected SP features. These measurements are achieved accurately and exhaustively, and this method offers an alternative to manual SP counting. We demonstrate its application to 4 cases spanning the full range of the severity of the disease.

Adult↗

PubMed1995

3-dimensional morphometry of intact dendritic spines observed in thick sections using an electron microscope.

An experimental technique is described which allows observation of fixed neuronal dendrites at magnifications from 10-12 K. The method uses 4-7-microns-thick sections of Epon-embedded tissue with nerve cells that are first impregnated by the rapid Golgi technique and then stained with gold particles/aggregates using a modified gold-toning procedure. A relatively high acceleration voltage (200 kV) is employed to observe in fine detail the dendritic fragments of interest at different angular positions in space, by using a eucentric goniometer stage with a tilt angle of +/- 45 degrees. Image analysis methodology is proposed which permits estimation of 3-dimensional (3D) lengths and of the volume of observed intact dendritic spines. The advantages of the technique with respect to 3D reconstruction methodology are discussed.

Animals↗

PubMed1982

Developmental morphometry and physiology of the rabbit vagus nerve.

The morphological and physiological features of the rabbit vagus nerve were studied at different ages after birth. The total fibre count is about 37,500 of which at birth 1-2% and in the adult animal approximately 10% are myelinated. In the postnatal period the cross-sectional area of the vagus grows to 5 times its perinatal size due to an increase of endoneural collagen, fibre growth and myelinization. The myelinization is most pronounced in the first 2 weeks after birth, axonal growth is predominant thereafter. The available data suggest that the begin of myelinization as well as the subsequent development of the myelin sheath are not dependent on axonal size. There seems to be no fundamental difference between the morphological development of the vagus and other peripheral nerves, e.g. the sciatic nerve of the rat. At birth the vagus nerve contains 2 fibre groups as can be measured from the compound action potential with conduction velocities of 11.4 and 0.9 m.s-1 respectively. Upon subsequent development the conduction velocity of these fibres increases to 31.9 and 1.2 m.s-1 in full-grown animals. THe compound action potential of the adult nerve implies 2 additional fibre groups with conduction velocities of 12.3 and 4.6 m.s-1 respectively. These two fibre populations develop gradually from 1 to 2 weeks after birth and arise probably from the slowest conducting, non-myelinated or C-fibres. It is concluded that the functional innervation of the sinoauricular node may be operational at birth as far as the cervical vagus nerve is concerned.

Action Potentials↗

PubMed1985

Developmental morphometry of the vagus nerve in the opossum.

Developmental morphology of the vagus nerve has been described for placental but not marsupial mammals such as the opossum which undergo even greater postnatal maturation. In the present study, the cervical vagus nerve of opossums from the seventh postnatal day to the adult were compared after 3% glutaraldehyde immersion, postfixation in osmium tetroxide and staining with uranyl acetate and lead citrate. At 7 days of age, axons were unmyelinated. Only 4 myelinated axons were present at the 25th postnatal day and by 50 days of age only 11% of adult values were reached. The number of Schwann cells increased from 105 at age 7 days up to 640 in the adult. The number of myelin lamellae surrounding the largest axons increased from 9 at 25 days up to 102 +/- 9 at adulthood. In the newborn kitten and rabbit, the number of myelinated vagal fibers comprised 10% (n = 326) and 18% (n = 653), respectively, of that reached in the adult animal. Comparable values are not obtained in the opossum until the 50th postnatal day.

Animals↗

PubMed1985

Differential rearing effects on rat visual cortex synapses. II. Synaptic morphometry.

An array of morphological measurements was made upon spine synapses in the upper 4 layers of occipital cortex of rats reared for 30 days after weaning in complex (EC), social (SC) or isolated (IC) environments. The mean length of the synaptic contact zone (post-synaptic density plus interpolated non-impregnated regions) was greater in layer IV of EC rats than in IC rats. SC rats were intermediate, not differing from other groups. There were no differences in these measures in other layers, nor were there differences in the mean area or perimeter of presynaptic terminals or postsynaptic processes, the relative frequency of headed vs sessile shaped spines, the length of the apposition between pre- and postsynaptic processes, or the ratio of perimeter to area (inverse roundness) of postsynaptic processes. Cleft width was greater in regions of the contact zone where postsynaptic density was present than in regions where it was absent (perforations), but, aside from the previously described differences in the frequency of perforated synapses, there were no group differences in cleft width. The maximum length of synaptic contact zones and the maximum area of presynaptic terminals was greater in EC than in IC rats in layer IV, but not in other layers, with SC rats again intermediate. These results support previous findings of larger layer IV synaptic contacts in EC rats and suggest that the size of some synaptic components can change without changes in others, a population of very large synapses is seen in layer IV of EC rats that is not seen in IC rats, and perforations may be unlikely sites of synapse splitting, given that membranes are more closely apposed in these regions, rather than pulling apart.

Animals↗

PubMed1993

Morphometry of rat olfactory bulbs stained for cytochrome oxidase reveals that the entire population of glomeruli forms early in the neonatal period.

Cytochrome oxidase staining selectively highlights the synapse-rich neuropil of olfactory bulb glomeruli. Detailed morphometric enumeration of glomeruli in cytochrome oxidase-stained sections from postnatally developing rats reveals that the entire adult population of glomeruli (2400/bulb) forms early in life, the process being complete by days 3-5 postnatal. Newborn's glomeruli range in diameter from a mean of about 50 microns to a maximum of about 70 microns and undergo a 3-fold increase in diameter and a 20-fold increase in volume during days 1-50 postnatal. The presence of the entire adult's glomeruli in the neonate calls for a serious revision of some current views on glomerular development and, given the critical roles of glomeruli as modules, the findings bear important implications for the organization of olfactory system and early development of olfactory functions.

Animals↗

PubMed1994

Anatomical-behavioral relationships: corpus callosum morphometry and hemispheric specialization.

We obtained midsagittal measures of the corpus callosum in 60 healthy young adults (right-handed and left-handed males and females), and examined whether individual differences in anatomical measures of callosal connectivity are related to behavioral laterality measures in the same subjects. In an attempt to tap functionally-distinct callosal "channels", four behavioral laterality tasks were used that differed in sensory modality (visual, auditory, tactile) and/or level of cognitive processing (sensory versus semantic). In addition, the tasks had both intrahemispheric and interhemispheric conditions. Sex differences were found for measures of the posterior body (i.e. isthmus) of the corpus callosum, which, in turn, interacted with handedness. In contrast, only handedness effects were found for the behavioral laterality measures. Anatomical-behavioral correlations did not disclose relationships between callosal size and performance on task conditions requiring sensory interhemispheric integration or transfer. Instead, the correlational findings are consistent with the view that the corpus callosum participates in such higher order "control" functions as the support of bilateral representation of language, functional interhemispheric inhibition, and the maintenance of hemispheric differences in arousal. This is consistent with the finding that regional callosal size is related to the number of small diameter fibers, which are presumed to interconnect homologous association cortices in the two hemispheres.

Adult↗

PubMed1993

Morphometry of gastric endocrine cells in hypergastrinemic patients treated with the somatostatin analogue octreotide.

The aim of the study was to evaluate whether treatment with 200 micrograms/d of the somatostatin analogue octreotide (SMS 201-995) for three months can influence the trophic action exerted by hypergastrinemia on endocrine cells of the oxyntic mucosa, a condition potentially leading to hyperplasia and carcinoid tumors. Endocrine cells were morphometrically investigated in Grimelius silver stained sections of endoscopic biopsies of oxyntic mucosa collected from 13 hypergastrinemic patients with Zollinger-Ellison syndrome (ZES) (n = 5), antral G cell hyperfunction (AGCH) (n = 4) and atrophic gastritis type A (AG-A) (n = 4) before and after 3 months treatment and 3 months after drug discontinuance. The treatment induced a reduction of the volume density (P < 0.015), profile cross sectional area (P < 0.05) and number of cell profiles per unit area (P < 0.015) of argyrophil cells. A rebound of all these parameters was observed 3 months after drug withdrawal with values usually exceeding those at the entry, except in cases of AG-A. The patients' plasma gastrin concentrations presented similar variations showing a significant relation with all morphometric parameters of argyrophil cells. Also, the cell content in alpha subunit of human chorionic gonadotropin was related to the plasma gastrin levels, a finding confirming the close gastrin dependence of the expression of this protein by oxyntic endocrine cells. No significant changes were observed in mucosal somatostatin D cells. These results indicate that variations in circulating gastrin levels are the most likely factor responsible for the hypotrophic effect of octreotide on oxyntic argyrophil cells (mostly corresponding to the ECL cells) of hypergastrinemic patients.

Adult↗